CARBONLETT, vol. 24, no. 1, pp.18-27, 2017

DOI: http://dx.doi.org/10.5714/CL.

Effect of the surface modification using MWCNTs with different L/D by two different methods of deposition on the IFSS of single carbon fiber-epoxy resin composite

Minerva L. Herrera-Sosa¹, Alex Valadez-González¹, Humberto Vázquez-Torres², Pierre G. Mani-González³ and Pedro J. Herrera-Franco^1,♠

Affiliation: ¹Unidad de Materiales, Centro de Investigación Científica de Yucatán A.C., Merida, Yucatan, 97205, Mexico
²Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, Ciudad de Mexico 09340, Mexico
³Departamento de Física y Matemáticas, Universidad Autónoma de Ciudad Juárez, Chihuahua, 32310, Mexico

Abstract: Multiwall carbon nanotubes (MWCNT) with two different (L/D) aspect ratios (7±2 μm/140±30 nm and 0.5-2 μm/8-15 nm) were surface treated using nitric acid (HNO3) and polyethyleneimine (PEI) prior to their deposition on carbon fibers (CF). Before the hierarchical reinforcement with CF-MWCNT, the CFs were treated with 3-glycidoxypropyltrimethoxysilane, a coupling agent (Z6040) and with poly(amidoamine) (PAMAM) a dendrimer containing an ethylenediamine core and amine surface groups. The MWCNT were deposited on the CF using two methods, by electrostatic attraction and by chemical reactions. The changes in the CF surface morphology after the MWCNT deposition were analyzed using SEM, which revealed a higher density and uniform coverage for the PAMAM-treated CF and the short MWCNTs. The interfacial adhesion of the composite materials was evaluated using the single fiber fragmentation technique. The results indicated an improvement in the interfacial shear strength with the addition of the short-MWCNTs treated with acid solutions and grafted onto the surface of the CF fiber using electrostatic attraction.

Keyword: carbon nanotubes, chemical treatment, carbon fibers, surface treatment